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  <?php
namespace Drupal\webform\Form;
use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Url;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
class WebformHelpVideoForm extends FormBase {
  use WebformDialogFormTrait;
  
  protected $helpManager;
  
  protected $videoId;
  
  public function getFormId() {
    return 'webform_help_video_form';
  }
  
  public static function create(ContainerInterface $container) {
    $instance = parent::create($container);
    $instance->helpManager = $container
      ->get('webform.help_manager');
    return $instance;
  }
  
  public function buildForm(array $form, FormStateInterface $form_state, $id = NULL) {
    $this->videoId = str_replace('-', '_', $id);
    $video = $this->helpManager
      ->getVideo($this->videoId);
    if (!$video) {
      throw new NotFoundHttpException();
    }
    $form['#title'] = $video['title'];
    
    if (is_array($video['content'])) {
      $form['content'] = $video['content'];
    }
    else {
      $form['content'] = [
        '#markup' => $video['content'],
      ];
    }
    
    if ($video['youtube_id']) {
      $form['video'] = [
        '#theme' => 'webform_help_video_youtube',
        '#youtube_id' => $video['youtube_id'],
      ];
    }
    
    if ($video_links = $this->helpManager
      ->getVideoLinks($this->videoId)) {
      $form['resources'] = [
        '#type' => 'details',
        '#title' => $this
          ->t('Additional resources'),
        'links' => [
          '#theme' => 'links',
          '#links' => $video_links,
        ],
      ];
    }
    
    if ($this
      ->isDialog()) {
      $form['modal_actions'] = [
        '#type' => 'actions',
      ];
      $form['modal_actions']['close'] = [
        '#type' => 'submit',
        '#value' => $this
          ->t('Close'),
        '#ajax' => [
          'callback' => '::closeDialog',
          'event' => 'click',
        ],
        '#attributes' => [
          'class' => [
            'button',
            'button--primary',
          ],
        ],
      ];
      if ($this
        ->getRequest()->query
        ->get('more') && $this
        ->currentUser()
        ->hasPermission('access webform help')) {
        $form['modal_actions']['more'] = [
          '#type' => 'link',
          '#title' => $this
            ->t('▶ Watch more videos'),
          '#url' => Url::fromRoute('webform.help'),
          '#attributes' => [
            'class' => [
              'button',
            ],
          ],
        ];
      }
    }
    $form['#attached']['library'][] = 'webform/webform.help';
    return $form;
  }
  
  public function validateForm(array &$form, FormStateInterface $form_state) {
    if ($this
      ->isDialog()) {
      $form_state
        ->clearErrors();
    }
    else {
      parent::validateForm($form, $form_state);
    }
  }
  
  public function submitForm(array &$form, FormStateInterface $form_state) {
    
  }
}